The present invention relates to remote control systems, particularly for controlling industrial equipment.
Known remote control systems of this class generally consist of a transmitter unit that is operated by a human operator and a receiver unit on the industrial equipment to be controlled, e.g., a crane, to which control signals from the control unit are transmitted by wire or wireless, particularly by radio. The receiver unit then converts the received control signals into the desired movements of the controlled industrial equipment.
The controlled industrial equipment consists largely of equipment that must be controlled in a very safety-oriented manner since, if controlled incorrectly, it can cause considerable damage, for example because of its size or because of the objects to be moved. It is therefore known to provide an xe2x80x9cemergency off switchxe2x80x9d in remote control systems of this type, which permits the operator to quickly terminate the controlled movement of the industrial equipment once an undesired operation has been detected, or to at least place the equipment into a waiting state until the cause of the undesired control or undesired movement has been determined.
This method of operation is reasonably reliable. However it presupposes that the operator is able to recognize a dangerous situation and activate the emergency off switch on the transmitter quickly enough. Known methods thus have two significant shortcomings:
Malfunctions of the human component in the xe2x80x9chuman-machinexe2x80x9d system are not detected, i.e., sudden health-related reactions by the operator, be it with or without the influence of the detected false operation of the controlled industrial equipment, can possibly prevent a timely activation of the emergency off switch and imminent damage may thus not be prevented in a timely or reliable manner.
Furthermore, the known system depends on the emergency off switch being an easily accessible part on the operating device, i.e., essentially depends on the operator holding the operating device in his hand.
Particularly in the case of radio remote control of industrial equipment, it is now also conceivable, however, to forgo the use of such a hand-held operating device and to have a voice-activated control, for which the transmitter does not necessarily need to be housed inside a hand-held operating device or may be eliminated completely.
The invention provides a novel control system that is particularly safety relevant and that makes control information available even when an emergency off switch in its classic form cannot be activated.
This and other objects are achieved according to the invention by a remote control system comprising: a sensor that detects an operator""s safety-relevant medical status and transmits data representing that status as a control signal; and a control circuit that receives the data and responds to data values indicating an inability of the operator to perform a control function to trigger a predefined control sequence.
It should thus be seen as an underlying concept of the present invention that even a malfunction of the xe2x80x9chuman componentxe2x80x9d in the overall system will be reliably detected as soon as it becomes safety relevant, i.e., as soon as there is a danger that the operator might no longer be able to control the industrial equipment properly and reliably with the remote control system.
This basic principle may also be used in classic hand-held operating devices; however, it also ensures a reliable emergency off function in conjunction, for example, with headsets for the voice-activated control of the given industrial equipment.
Depending on the chosen design of the transmitter operating element, a sensor that is used to detect the operator""s state of health may be installed either directly in a housing together with the other electronic transmitter components, or it may be disposed separately at a location where a particularly reliable detection of medical information regarding the operator""s state of health is possible, particularly medical information that represents a measure for the operator""s current stress situation. The sensor may thus be housed inside a component that is spatially separate from the transmitter unit, e.g., in a cuff fastened around the operator""s wrist that measures the operator""s pulse rate, either continuously or at predefinable intervals.
According to certain embodiments of the invention, the system may be provided with a memory unit storing the medical data that is produced over at least one predefinable interval, and a computing element that obtains from the stored medical data information that is used to individually cause at least one of the control signal and the data values to be effective for activation of the predefined control sequence in order to conform the system to the medical status of a given operator. These components may be installed in the transmitter or the receiver.